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This is an approved experiment which is scheduled for the year 2000 at MAMI in Mainz as part of the TAPS experimental campaign.
A tagged photon beam will hit a liquid helium target. The Delta resonance which can be excited when a nucleon is hit inside the helium nucleus will decay into pion and nucleon.
The neutral pion will be detected by its two decay gamma rays in the TAPS detector to the left side of the beam. Neutrons but also protons are to be measured with the scintillator detectors of the TOF walls.
This is a sketch of the experimental floor plan.
It is still being optimized, and common solutions are looked for to minimize changes between different experiments.
The aim of this experiment is to detect possible changes in the properties (i.e. mass, lifetime) of the Delta resonance as it is produced not on its own but with surrounding nucleons.